How to Ensure Water Safety Control in Beverage Processing?

How to Ensure Water Safety Control in Beverage Processing?

In various food and beverage manufacturing processes, water serves not only as a key ingredient in product formulation but also for cleaning and disinfecting processing equipment, facilities, and tools.

For instance, products like mineral water, carbonated beverages, fruit juices, vegetable juices, milk, beer, and wine consist largely of water.

Water also plays a vital role in manufacturing canned goods and tofu, functioning as one of their primary components. Although water is not the primary component in products like candies, pastries, bread, and cookies, it significantly impacts product quality during production.

Therefore, to a certain extent, water sanitation in food factories is a crucial aspect of food hygiene, and food quality is closely related to the quality of water used in food processing.

Before discussing safety controls for production water in food enterprises, let's first understand the requirements for water used in food processing:

1. Drinking water must be free of pathogenic microorganisms;

2. Chemical substances in drinking water must not endanger human health;

3. Radioactive substances in drinking water must not endanger human health;

4. Water must possess good sensory characteristics and undergo disinfection treatment;

5. Water quality must meet standard requirements.

For example:

(1) Bacteriological indicators: Must be free of pathogenic bacteria, with very low total bacterial counts. Total bacteria must not exceed 100 per ml, and coliform bacteria must not be detected;

(2) Toxicological indicators: Levels of toxic components (e.g., fluoride, cyanide, arsenic, selenium, mercury, cadmium, lead, chromium) must not exceed specified limits;

(3) Chemical indicators: pH must be suitable, typically between 6.5 and 8.5, with a refreshing taste and meeting specific hardness requirements. Additionally, concentrations of iron, manganese, zinc, copper, and other ions must be restricted;

(4) Appearance: Must be colorless and odorless, free of visible substances—including suspended solids, surface floats, sediments, microorganisms, and immature larvae.

Next, let us explore safety controls for production water in food enterprises. We welcome contributions to address any shortcomings.

National Food Safety Standard: General Hygiene Specifications for Food Production (GB 14881-2013) 5.1.1 stipulates:

5.1.1.1 "Water quality, pressure, volume, and other requirements shall meet production needs. 5.1.1.2 Water quality for food processing shall comply with GB 5749. Foods with special water quality requirements shall meet corresponding regulations. Water quality for indirect cooling water, boiler feedwater, and other production uses shall satisfy production needs.

5.1.1.3 Water used for food processing shall be conveyed through completely separate piping systems from other non-food-contact water (such as indirect cooling water, sewage, or wastewater) to prevent cross-contamination. Each piping system shall be clearly labeled for identification.

5.1.1.4 Self-supplied water sources and water supply facilities shall comply with relevant regulations. Products used in water supply facilities that involve drinking water hygiene safety shall also comply with relevant national regulations.

1 Water Source Requirements

Generally, there are three types: seawater, private wells, and municipal water supply. The latter two are more commonly used. Municipal water supply has well-controlled water quality but is relatively expensive. Private wells are relatively inexpensive, but water quality control should be strengthened.

For the packaged drinking water industry, purified water and mineral water mostly use municipal water networks, with some using surface water or groundwater. while natural water and (mountain) spring water originate from surface or groundwater sources, and mineral water exclusively from groundwater or natural springs.

Based on industry practices, GB 19398-2014 stipulates: "For source water originating from non-public water supply systems (surface or groundwater), its quality must meet the sanitary requirements for drinking water sources specified in GB 5749; After treatment, the quality of water used for food processing shall comply with GB 5749." That is, when surface water or groundwater from non-public water supply systems is used as production source water, its quality shall comply with GB 3838 or GB/T 14848.

2. Storage Facility Requirements

Production water is typically stored in reservoirs or storage tanks. Reservoirs require enhanced management; wooden lids and chain seals are inadvisable (poor sealing facilitates contamination). Storage facilities must undergo regular cleaning and disinfection. Water may only be used after passing quality inspection, with records of cleaning, disinfection, and water quality testing retained.

Given the high cost of constructing water towers and their periodic cleaning/disinfection requirements, general enterprises may consider installing a secondary water supply system. This involves installing multiple standby pumps within the same water supply line. During high-demand periods, all pumps can operate simultaneously; during low-demand periods, only one or two pumps are activated. This flexible installation design ensures water supply needs are met while reducing water supply costs.

3. Pipeline Design

Non-potable water may be used for factory boilers, firefighting, and landscaping. However, potable water, non-potable water, and wastewater pipelines must be strictly segregated without cross-contamination, clearly color-coded for identification. The company should develop a detailed water supply network diagram, explicitly labeling supply codes and clearly indicating pipeline layout and routing to facilitate management and maintenance of the production water system.

Plastic flexible water hoses used in workshops must be made of safe, non-toxic materials. They should not be dragged on the floor and must be stored on dedicated racks after use. Anti-siphon devices installed within filtration units on workshop main supply lines effectively prevent backflow. Workshop water pipes must be positioned at least twice their diameter above water surfaces. Direct insertion of flexible hoses into sinks within workshops is prohibited.

4. Production Process Water Management

1. Ingredient Water

Ingredient water must be purified water. Another potential source of water contamination in food environments is water softening and deionization equipment. If water exhibits off-odors, this should be the primary consideration. In such cases, coliform monitoring may be negative, yet total bacterial counts may be exceptionally high. Softened water can become cloudy or even dark due to bacterial contamination. Remediation involves frequent backwashing of resin layers and regular replacement.

2. Ice and Steam

Water used for producing ice and steam must comply with the national “Drinking Water Standards.” Materials for ice-making equipment should be rust-resistant and non-toxic, while ice storage containers must be clean and hygienic.

Steam delivery pipes must be made of rust-resistant materials, maintained hygienically, and kept in good condition—robust, durable, and leak-free to prevent hazards to personnel safety and product quality. When using steam heating, direct contact with food ingredients should be avoided. Double-walled vessels can be employed to minimize complex requirements. Where steam directly contacts food, filtered steam or clean steam must be used, determined by process requirements and product quality standards.

3. Cleaning and Disinfection Water

The ideal water source for raw material rinsing is microorganism-free, pH-neutral, and low in mineral content, including hot water (minimum 82°C or higher) and cold water, with relatively high pressure requirements. However, requirements vary depending on usage conditions. To achieve disinfection and sterilization, the effective chlorine concentration in circulating water used for raw material rinsing is generally 20–25 ppm, while the effective chlorine concentration in sterilizing cooling water is typically 3–5 ppm. The residual chlorine concentration in sterilizing cooling discharge water is generally 0.5–1.0 ppm. In beverage and juice production processes, ozonated water may also be used for soaking and rinsing pipelines, production equipment, and storage containers.

5 Wastewater Discharge

Wastewater must undergo appropriate treatment prior to discharge to comply with national standards (e.g., GB8978-1996 Comprehensive Standards for Wastewater Discharge). Wastewater treatment tanks should be located away from production workshops.

Workshop drainage interfaces with external systems must be fitted with metal mesh covers to prevent mosquitoes, flies, and insects. Floor drains and drainage channel outlets should employ P, U, or S-type traps with water seals to prevent odors. Wastewater flow direction should proceed from high-cleanliness zones to low-cleanliness zones.

The wastewater from the upstream process in the food enterprise's treatment system does not exhibit whitening. However, the water in the final sedimentation tank shows some whitening. The effluent tests indicate relatively low levels of ammonia nitrogen and COD. The chemicals used are polyacrylamide and polyaluminum chloride, with light calcium carbonate and sodium hydroxide used to adjust the pH.

Expert Q&A: Does the influent water quality fluctuate or exhibit significant compositional variations? If high sugar content is present, whitening may occur due to protein hydrolysis. If excessive degradable organic matter is present, process modification is recommended. Flocculation and sedimentation are physical-chemical reactions; certain degradable organic compounds cannot be removed through this process.

6. Monitoring Requirements

During production, water samples should be sequentially collected from production areas for testing of microbiological content, turbidity, odor and taste, visible particles, pH, etc.

Effective chlorine levels in raw material washing process recirculating water and sterilizing cooling water must be measured hourly. Sterilizing cooling discharge water must be tested per batch.

At least once annually, submit processing water to a qualified testing department for comprehensive testing according to standards (mineral water sources must comply with GB8537; other water sources must comply with GB 5749).